AIRCRAFT TOTAL AIR TEMPERATURE ANOMALY DETECTION

• US 20160370236A1
• Filed: 06/22/2015
• Published: 12/22/2016
• Est. Priority Date: 06/22/2015
• Status: Abandoned Application

• Current Assignee: Rosemount Aerospace, Inc. (Rtx Corporation)
• Original Assignee: Rosemount Aerospace, Inc. (Rtx Corporation)
• Inventors: Nelson, Jordan William, Schwie, Chester, Daup, Michael Robert
• Application Number:
  US14/745,798
• Publication Number:
  US 20160370236A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01K 13/028 for use in total air temperature [TAT] probes
• CPC Class Codes: G01K 15/007 Testing

Abstract

An example method includes receiving, by a computing device, an indication of a measured total air temperature (TAT) from a temperature probe installed on an aircraft. The method further includes determining, by the computing device, a theoretical temperature corresponding to conditions at which the TAT is measured, and determining, by the computing device, a measured TAT anomaly condition based on the measured TAT and the theoretical temperature corresponding to the conditions at which the TAT is measured.

Claims

1. A method comprising:

receiving, by a computing device, an indication of a measured total air temperature (TAT) from a temperature probe installed on an aircraft;

determining, by the computing device, a theoretical temperature corresponding to conditions at which the TAT is measured; and

determining, by the computing device, a measured TAT anomaly condition based on the measured TAT and the theoretical temperature corresponding to the measured TAT.

2. The method of claim 1, wherein the theoretical temperature corresponding to the conditions at which the TAT is measured comprises a theoretical TAT;

and

wherein determining the theoretical temperature corresponding to the conditions at which the TAT is measured comprises determining the theoretical TAT based on a measured altitude of the aircraft and a measured Mach number of the aircraft.

3. The method of claim 2, wherein determining the theoretical TAT based on the measured altitude of the aircraft and the measured Mach number of the aircraft comprises determining an international standard atmosphere (ISA) TAT based on the measured altitude of the aircraft and the measured Mach number of the aircraft.

4. The method of claim 3, wherein determining the ISA TAT comprises determining the ISA TAT according to the following equation:

ISA_TAT=SAT×

(1+0.2×

M²);

wherein SAT is a static air temperature; and

wherein M is the measured Mach number of the aircraft.

5. The method of claim 4, wherein determining the ISA TAT further comprises determining SAT according to the following equation:

6. The method of claim 2, wherein determining the measured TAT anomaly condition comprises determining the measured TAT anomaly condition in response to determining that the measured TAT exceeds a threshold deviation from the theoretical TAT.

7. The method of claim 2, further comprising:

determining, by the computing device, a rate of change of a difference between the measured TAT and the theoretical TAT with respect to time;

wherein determining the measured TAT anomaly condition comprises determining the measured TAT anomaly condition in response to determining that the rate of change of the difference between the measured TAT and the theoretical TAT with respect to time exceeds a threshold deviation rate.

8. The method of claim 2, further comprising:

determining, by the computing device, a measured TAT rate as a rate of change of the measured TAT with respect to time;

determining, by the computing device, a theoretical TAT rate as a rate of change of the determined theoretical TAT with respect to time; and

determining, by the computing device, a ratio of the measured TAT rate to the theoretical TAT rate;

wherein determining the measured TAT anomaly condition comprises determining the measured TAT anomaly condition in response to determining that the ratio of the measured TAT rate to the theoretical TAT rate exceeds a threshold ratio deviation.

9. The method of claim 1,

wherein the theoretical temperature corresponding to the conditions at which the TAT is measured comprises a theoretical static air temperature (SAT);

and

wherein determining the theoretical temperature corresponding to the conditions at which the TAT is measured comprises determining the theoretical SAT based on a measured altitude of the aircraft.

10. The method of claim 9, wherein determining the theoretical SAT based on the measured altitude of the aircraft comprises determining an international standard atmosphere (ISA) SAT based on the measured altitude of the aircraft.

11. The method of claim 10, wherein determining the ISA SAT comprises determining the ISA SAT according to the following equation:

12. The method of claim 9, further comprising:

determining, by the computing device, a measured SAT based on the received measured TAT and a measured Mach number of the aircraft according to the following equation;

13. The method of claim 12, wherein determining the measured TAT anomaly condition based on the measured SAT and the theoretical SAT comprises determining the measured TAT anomaly condition in response to determining that the measured SAT exceeds a threshold deviation from the theoretical SAT.

14. The method of claim 12, further comprising:

determining, by the computing device, a rate of change of a difference between the measured SAT and the theoretical SAT with respect to time;

wherein determining the measured TAT anomaly condition based on the measured SAT and the theoretical SAT comprises determining the measured TAT anomaly condition in response to determining that the rate of change of the difference between the measured SAT and the theoretical SAT with respect to time exceeds a threshold deviation rate.

15. A computing device comprising:

at least one processor; and

computer-readable memory encoded with instructions that, when executed by the at least one processor, cause the computing device to;

receive an indication of a measured total air temperature (TAT) from a temperature probe installed on an aircraft;

determine a theoretical temperature corresponding to conditions at which the TAT is measured; and

determine a measured TAT anomaly condition based on the measured TAT and the theoretical temperature corresponding to the conditions at which the TAT is measured.

16. The computing device of claim 15,

wherein the theoretical temperature corresponding to the measured TAT comprises a theoretical TAT;

and

wherein the instructions to determine the theoretical temperature corresponding to the conditions at which the TAT is measured comprise instructions that, when executed by the at least one processor, cause the computing device to determine the theoretical TAT based on a measured altitude of the aircraft and a measured Mach number of the aircraft.

17. The computing device of claim 16, wherein the instructions to determine the measured TAT anomaly condition comprise instructions that, when executed by the at least one processor, cause the computing device to determine the measured TAT anomaly condition in response to determining that the measured TAT exceeds a threshold deviation from the theoretical TAT.

18. The computing device of claim 16,

wherein the computer-readable memory is further encoded with instructions that, when executed by the at least one processor, cause the computing device to determine a rate of change of a difference between the measured TAT and the theoretical TAT with respect to time;

and

wherein the instructions to determine the measured TAT anomaly condition comprise instructions that, when executed by the at least one processor, cause the computing device to determine the measured TAT anomaly condition in response to determining that the rate of change of the difference between the measured TAT and the theoretical TAT with respect to time exceeds a threshold deviation rate.

19. The computing device of claim 16,

wherein the computer-readable memory is further encoded with instructions that, when executed by the at least one processor, cause the computing device to:

determine a measured TAT rate as a rate of change of the measured TAT with respect to time;

determine a theoretical TAT rate as a rate of change of the determined theoretical TAT with respect to time; and

determine a ratio of the measured TAT rate to the theoretical TAT rate;

wherein the instructions to determine the measured TAT anomaly condition comprise instructions that, when executed by the at least one processor, cause the computing device to determine the measured TAT anomaly condition in response to determining that the ratio of the measured TAT rate to the theoretical TAT rate exceeds a threshold ratio deviation.

20. The computing device of claim 15, wherein the theoretical temperature corresponding to the conditions at which the TAT is measured comprises a theoretical static air temperature (SAT);

wherein the instructions to determine the theoretical temperature corresponding to the conditions at which the TAT is measured comprise instructions that, when executed by the at least one processor, cause the computing device to determine the theoretical SAT based on a measured altitude of the aircraft;

wherein the computer-readable memory is further encoded with instructions that, when executed by the at least one processor, cause the computing device to determine a measured SAT based on the received measured TAT and a measured Mach number of the aircraft; and

wherein the instructions to determine the measured TAT anomaly condition comprise instructions that, when executed by the at least one processor, cause the computing device to determine the measured TAT anomaly condition based on at least one of;

a comparison of the measured SAT to the theoretical SAT; and

a comparison of a rate of change of a difference between the measured SAT and the theoretical SAT with respect to time to a threshold deviation rate.